I have several pairs of images that make up a single image. I know how to join the images to make a larger JPG. But for most of the time I am content to view the images separately so I don't want to go to the trouble (or waste the disk space) of joining the pairs.
However it would be nice to have a program that would allow me to temporarily view a pair side by side without any visible seam.
So far Google has failed me - probably because what I want does not exist.
I refuse to use Processing because it does not allow the use of an external editor. If a Processing program could run on an Android tablet I might change my mind.